The need for the new capability has been sought in data centers -- there are many Windows-based applications, including many made by IBM, that interact with mainframes to access data. Such applications must now be managed separately.

IBM said the new support for Windows will boost the security and speed of mainframe-based corporate environments. It will provide users with the ability to connect systems on a private network, to avoid other network hops, and to have integrated management.

Greg Lotko, business line executive of IBM's System z Division, said the addition of Windows support "is really recognizing that the world is heterogeneous." The System z platform now supports z/OS, Linux, Unix and Windows, he added.

Joe Clabby, an analyst at Clabby Analytics, sees benefits for users.

System z is known for its ability to run transaction and batch workloads, while Linux is good for Java workloads. But the other thing that System z does is extend its governance out to the zBX blades "and that makes it easier to integrate and work with that data."

Clabby said combined management capabilities will reduce the labor required to run mainframe environments with multiple operating systems. "If you can manage this as a single architecture, it saves money," he said.

Jean Bozman, an analyst at IDC, said Windows support will allow for very fast connections between the Windows apps and the mainframe. "You will get faster performance and end-to-end management," she said.

Bozman said IBM's decision to provide Windows support confirms IBM's view that the distributed and mainframe worlds are becoming closer.

Patrick Thibodeau covers SaaS and enterprise applications, outsourcing, government IT policies, data centers and IT workforce issues for Computerworld. Follow Patrick on Twitter at @DCgov, or subscribe to Patrick's RSS feed. His email address is pthibodeau@computerworld.com.